lst={'root':'123456','admin':'admin'}
while True:
    usrname=(input("欢迎使用用户检测系统(输入quit退出系统)\npls input user name: "))
    if usrname == "quit": break
    pwd=(input("pls input password: "))
    if pwd==lst.get(usrname):
        print("验证成功")
    else:
        print("验证失败")